It is known to use a sub-panel, mounted adjacent the main service panel, to add a second power source for designated circuits in the event power from the utility company is disrupted. The sub-panel includes a primary breaker or disconnect switch which receives power from the main service panel and an auxiliary breaker or disconnect switch for receiving power provided by an auxiliary power source, such as a generator. The primary and auxiliary breakers are generally arranged in tandem such that a bar or linkage connecting the operating mechanisms of the two breakers will operate both simultaneously. The breakers are also generally positioned such that either the ON or the OFF positions of both breakers are immediately adjacent one another thus permitting only one breaker to be ON at a time. Devices such as this are taught in U.S. Pat. No. 5,648,646 to Flegel, which issued Jul. 15, 1997, and in a brochure describing the manual transfer panels manufactured by Eylander Electric of Everett, Washington. The assignee of the present invention also manufactures manual transfer sub-panels of a similar design which are sold under Square D Catalog Numbers QO4-8M30DSGP and QO4-8M60DSGP.